Composition of plaster.



-UNITED STATES PATENT OFFICE.

CHARLES R. HARRIS AND CHRISTOPHER G. BARRICK, CF LOS ANGELES,

CALIFORNIA.

Specification of Letters Patent.

Application on June 2. 1903. Burial Ho. 159,809.

To all whom it may concern:

Be it known that we CHARLES R. HARRIS and Onms'rornnn O. :ARRICK,residents of Los Angeles, inthe county of Les An eles and State ofCalifornia, have invents *certain new and useful Improvements inCompositions of Plaster; andwe do hereby declare the following to be afull, clear, and exact description of the invention, such as will enformof a dry powder to be mixe with watcrv for use.

The base of our im rovedcomposition is clay, and this is mixe intheproper pro ortions with cement, calcined plaster, and fl er.

These proportions me be as follows: clay, seven hundred to one t ousandpounds; calcined plaster, three hundred to nine hundred ounds; cement,one hundred and fifty to our hundered pounds, anda suitable uantity offiber, which ma be asbestos ber, wood fiber, or other suite. is fibrousmaterial, and a suitable retarder may also be added. A preferred proortion is'clay, one thousand pptunds, calcine plaster, seven hundred andy pounds; cement, two hundred and fifty ounds; and sufficientfiber tomake a hinder or the mass, this varying in amount according to thecharacter of the fiber used. If hair or jute fiber is used, from threeto five ounds to the ton will answer, while if wood her is used fromfifty to one hundred pounds to the ton can be used to good advantage,and stucco-retarder may be added to suit conditions.

Our im roved composition is preferably mixed an shipped dry in the formof a powder and can be mixed with water and a suitable coloring-matter,or the coloring-matter ma be added before shipment, if desired.

he primary object of a wall-covering is cheapness, strength, anon-conductor of heat, cold electricity, and sound, and its inherentqllaijghty of being water and fire proof. In t composition we secure allthese qualities to one thousand and in addition produce a plaster whichis hard and firm, yet not brittle or resonant, and

will not warp or crack if exposed to the" weather. In has great.adhesive qualities to adhere to lathed, wired, or plain walls and withwhich either a rough or smooth highlypolished surface can be produced.It will s read easily and will provide extra long cl enches to securelyhold the plaster in ppsition without'danger of the clenches brea ing offwhen. dry. It can also be molded in any form and canbe formed in platesor sheets and sawed into suitable lengths and secured to the wall bynails or screws, and, as before stated, it can be mixed and shipped in adry state for use. 1

Various changes might be made in the relative proportions of t e severalingredients set forth, and hence we do not wish to be limited to theprecise proportions stated.

Having thus fully described our invention, what we claim as new, anddesire to secure by Letters Patent, is-' 1. A dry powder for plaster,consistin of clay in the proportion o from seven. hun red ounds,calcined plaster in the pro ortion of irom three, hundred to nine hundrepounds, cement in the proportion of from one hundred and fifty to ourhundred pounds and fiber in the proportion substantially as specified.

2. A dry powder for luster, consistin of clay in the proportion o fromseven hun red to one thousand pounds, calcined plaster in the pro ortionof from three hundred to nine hundre pounds, cement in the roportion offrom one hundred and fifty to our hundred pounds, fiber in theproportion substantially as specified and a retarder.

3. A dry powder for laster, consisti cr of clay in the proportion o fromseven hun red to one thousand pounds, calcined plaster in the proportionof from three hundred to nine hundred pounds, and cement in the proortion of from one hundred and fifty to our hundred pounds.

In testimony whereof we have signed this specification in the presenceof two subscribing witnesses.

CHAS. R. HARRIS. CHRISTOPHER C. BARRICK.

I Witnesses:

M. L. Ccsnms, CARL PAULY.

Patented June 19, 1906.

